1 files changed, 142 insertions, 0 deletions
diff --git a/liblights/lights.c b/liblights/lights.c
new file mode 100644
index 0000000..bd952a7
--- /dev/null
+++ b/liblights/lights.c
@@ -0,0 +1,142 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ * Copyright (C) 2012 The CyanogenMod Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "lights"
+#define LOG_NDEBUG 0
+
+#include <cutils/log.h>
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <hardware/lights.h>
+
+static pthread_once_t g_init = PTHREAD_ONCE_INIT;
+static pthread_mutex_t g_lock = PTHREAD_MUTEX_INITIALIZER;
+
+char const *const LCD_FILE = "/sys/class/backlight/panel/brightness";
+
+void 
+init_g_lock(void)
+{
+	pthread_mutex_init(&g_lock, NULL);
+}
+
+static int 
+write_int(char const *path, int value)
+{
+    int fd;
+    static int already_warned = 0;
+
+    fd = open(path, O_RDWR);
+    if (fd >= 0) {
+        char buffer[20];
+        int bytes = sprintf(buffer, "%d\n", value);
+        int amt = write(fd, buffer, bytes);
+        close(fd);
+        return amt == -1 ? -errno : 0;
+    } else {
+        if (already_warned == 0) {
+            LOGE("write_int failed to open %s\n", path);
+            already_warned = 1;
+        }
+        return -errno;
+    }
+}
+
+static int
+is_lit(struct light_state_t const* state)
+{
+    return state->color & 0x00ffffff;
+}
+
+static int 
+rgb_to_brightness(struct light_state_t const *state)
+{
+	int color = state->color & 0x00ffffff;
+
+	return ((77*((color>>16) & 0x00ff))
+		+ (150*((color>>8) & 0x00ff)) + (29*(color & 0x00ff))) >> 8;
+}
+
+static int 
+set_light_backlight(struct light_device_t *dev,
+			struct light_state_t const *state)
+{
+	int err = 0;
+	int brightness = rgb_to_brightness(state);
+
+	pthread_mutex_lock(&g_lock);
+    LOGD("set_light_backlight brightness=%d\n", brightness);
+	err = write_int(LCD_FILE, brightness);
+	pthread_mutex_unlock(&g_lock);
+
+	return err;
+}
+
+static int close_lights(struct light_device_t *dev)
+{
+	LOGV("close_light is called");
+	if (dev)
+		free(dev);
+
+	return 0;
+}
+
+static int open_lights(const struct hw_module_t *module, char const *name,
+						struct hw_device_t **device)
+{
+int (*set_light)(struct light_device_t* dev,
+            struct light_state_t const* state);
+
+    if (0 == strcmp(LIGHT_ID_BACKLIGHT, name)) {
+        set_light = set_light_backlight;
+    }
+    else {
+        return -EINVAL;
+    }
+
+    pthread_once(&g_init, init_g_lock);
+
+    struct light_device_t *dev = malloc(sizeof(struct light_device_t));
+    memset(dev, 0, sizeof(*dev));
+
+    dev->common.tag = HARDWARE_DEVICE_TAG;
+    dev->common.version = 0;
+    dev->common.module = (struct hw_module_t*)module;
+    dev->common.close = (int (*)(struct hw_device_t*))close_lights;
+    dev->set_light = set_light;
+
+    *device = (struct hw_device_t*)dev;
+    return 0;}
+
+static struct hw_module_methods_t lights_module_methods = {
+	.open =  open_lights,
+};
+
+const struct hw_module_t HAL_MODULE_INFO_SYM = {
+	.tag = HARDWARE_MODULE_TAG,
+	.version_major = 1,
+	.version_minor = 0,
+	.id = LIGHTS_HARDWARE_MODULE_ID,
+	.name = "Espresso10 Lights Module",
+	.author = "The CyanogenMod Project",
+	.methods = &lights_module_methods,
+};